When large values of torque and power are required in a motor-driven system, the conventional solution is to use one, large, and hence more powerful motor in place of a smaller and less powerful motor. Due to the physical constraints imposed on motor design and manufacture, however, the ratio of torque to inertia deteriorates as motor size increases, resulting in a lower peak acceleration rates with increased motor size. Thus, while the torque and power of the larger engine may be more suited to meet the requirements of the motor-driven system, the peak acceleration rate for the motor that may be unacceptable for the system. To overcome this undesired side effect, it has been conventional practice to modify motor design, for instance through the use of state-of-the-art materials and motor construction techniques, in order to maximize the performance achievable in a single motor. However, these practices are oftentimes limited in their ability to achieve the desired or lower equivalent inertia, with unsatisfactory results, particularly in motor-driven systems where there is a requirement for higher peak acceleration rates, such as systems demanding rapid changes in motion. There consequently remains a continuing need to improve the performance of motor-driven systems beyond that level presently attainable.